Hydraulic transmission mechanism



April 23, 1940. E ROSE HYDRAULIC TRANSMISSION MECHANISM Filed Sept; 28, 1957 .ll'Sheets-Sheet 1 IIIII April 23, 1940. E. L. ROSE 2,198,515

HYDRAULIC TRANSMISSION MECHANISM Filed Sept 28. 1937 11 Sheets-Sheet 2 Ill VEIIHWI war-1:.

Filed Sept. 28, 1937 /74 iii /a/ 7 21204 17/5714 a: L. fiasf,

Aprii 23, 1940. E. ROSE HYDRAULIC TRANSMISSION MECHANISM vl1 Sheets-Sheet 4 Filed Sept. 28, 193'! April 23, 1940. E. L. ROSE HYDRAULIC TRANSMISSION MECHANISM Filed Sept. 28, 1937 ll Sheets-Sheet 5 [257 4 6: A fiosz;

April 23, 1940.

E. L. ROSE 2,198,515

HYDRAULIC TRANSMISS ION MECHAN I SM Filed Sept. 28, 1937 ll Sheets-Sheet 6 3 MW [0.5721 a5 1. 50.5.4;

April 23, 1940.

E. L. ROSE 2,198,515 HYDRAULIC, TRANSMISSION MECHANISM Filed Sept. 28, 19s! 11 Sheets-Sheet April 23, 1940. E, L, ROSE 2,198,515

HYDRAULIC TRANSMISSION MECHANISM Filed Sept. 28, 1937 .lISheets-Sheet 8 wig/22% Z5 April 23, 1940. E. ROSE I 2,198,515

7 HYDRAULIC TRANSMISSION MECHANISM Filed Sept. 28, 1937 11 Sheets-Sheet 1O Filed Sept. 28. 19s? 11 Sheets-Shet 11 Patented Apr. 23, 1940 -STATES time Claims.

This invention relates to a hydraulic transmission mechanism and has for its object to provide, in a manner as hereinafter set forth, a mechanism of such class for transmitting motion 5 from a prime mover to a driven element capable of being controlled to operate at any desired-speed and in any desired direction.

The invention further aims to provide, in a manner as hereinafter set forth, a hydraulic transmission mechanism which eliminates the use of pintle bearings; whereby all heavy loads may be carried on anti-friction bearings; whereby it requires a very small quantity of hydraulic fluid for operation and will not unduly heat; whereby iii thrust adjustment passes through the center of the temperature generating zone and will be equally affected by temperature changes along with the parts it is holding to contact, thereby maintaining proper running conditions regardless 9b of temperature changes; and whereby overload is automatically controlled to prevent impairment of any of the parts thereof.

The invention further aims 'to provide, in a manner as hereinafter set forth, a mechanism ofthe class referred to having its parts so related to give a smooth and infinitely variable eifect and at the same time provide in a single mechanism the functions of a clutch and change speed gear Y effect whilst eliminating their undesirable feaga tures.

A further object of the invention resides in the employment .of a stationary highly efiicient and free running fluid transfer element or valve pressures, and in which the running clearances are not materially affected by temperature changes in its, or its associated parts, and inwhich the clearance may be easily adjusted for o wear or different fluid viscosities.

Another object of the invention is to provide an improved form of cylinder which allows a more compact and a more open construction for heat dissipation. 45 Another object of the invention is to provide an auxiliary by-pass channel with an overload valve that will greatly reduce the initial fluid pressure when circulating therein, thus preventing any undue temperature rise in the fluid. M A still further object of the invention is to place a power intensifier in the stroke control mechanism to reduce the efforts of the operator in manipulating the control.

A still further object of the invention is to v provide a variable speed gear which is easy to control and remains unusually cool in operation.' i

Further objects of the invention are to provide, in a manner as hereinafter set forth, a hydraulic transmission mechanism which is com- 5 paratively simple in its construction and arrangement, strong, durable, compact, smoothly operating, thoroughly emcient in its use, readily assembled, capable of being conveniently repaired when occasion requires, and comparatively inexpensive to set up.

To the above ends essentially and to others I which may be hereinafter referred to, the invention consists of the novel construction, combination and arrangement of parts as will be more specifically referred to and are, illustrated in the accompanying drawings wherein-is shown an embodiment of the invention, but it is to beunderstocd that changes, variations and modifications may be resorted to which fall within the scope of the invention as claimed.

In the drawings:

Figure 1 is a front elevation broken. away for the purpose of showing rear parts of the transmission,

Figure 2 is a fragmentary sectional view on line *2-2, Figure 1,

Figure 3 is a detail view in elevation looking towards one of the ends of the cylinder for housing the shifting piston for the pump or the motor 0 element,

Figure 4 is a section on line fl-t, Figure 1,

Figure 5 is a section on line 5-5, Figure 4,

Figure 6 is a fragmentary section on line 66, Figure 1,

Figure 7 1s a fragmentary section, broken away, on line 'l'l, Figure 1,

Figure 8 is an enlarged detail section on line 8-8, Figure 4,

Figure 9 is an enlarged detail section on line 9-9, Figure 4,

Figure 10 is an enlarged detail section on line Ill-40, Figure 4,

Figure 11 is an enlarged detail section on line ll-ll, Figure 4,

Figure 12 is a fragmentary section upon an enlarged scale on the line i2l2, Figure 11,

Figure 13 is a view of the structure shown in Figure 12 partly in front elevation and partly in section. 50

Figure 14 is a longitudinal sectional view illustrating the form of connection employed for the control rods,

Figure 15 is a section on line 85-65, Figure 1,

Figure 16 is a bottom plan of the transmission,

Figure 17 is an elevation from the left of Figure 1 with several of the parts removed,

Figure 18 is a. fragmentary section on line l8--l8 of Figure 6,

Figure 19 is a side elevation of the piston employed for shifting the motor element,

Figure 20 is a top plan view of the piston shown in Figure 19,/ I

Figure 21 is a section on line 2l-2l, Figure '7, Figure 22 is an elevation looking towards the inner face of an end support, Figure 23'is a section on line 23-23, Figure 24 is a perspective view illustrating the form of each of the hangers forming elements of section taken on 31-31, Figure 2, 30

Figure 32 is a fragmentary section illustrating the drive for the operating means of the fluid pump, and

Figure 33 is a sectional plan illustrating the coupling block forming an element of the suspension for the motor unit.

Figure 1 of the drawings illustrates in side elevation ahydraulic transmission mechanism, in

accordance with my invention. The transmission includes two units of like construction which are shown, one to be driven continuously in one direction, acting as 'a variable volume pump, the other acting as a variable speed motor, capable of being driven in either direction by a hydraulic coupling with the pump unit through a transfer a driven member or machine in which it is desired to vary the ratio of speed and torque or make reversals with the prime mover operating continuously in one-direction. It is also adapted to be controlled by varying the crank throw in both the pump and motor, this control being so constructed that after the pump has been moved into its full throw range in either direction, it will be followed up with a shortening of the motor crank throw which will give a further increase in speed' at the sacrifice of torque, but should be limited to a two to one overdrive.

The mechanism includes a horizontally disposed rectangular platform or support I which is mounted at its sides on a pair of spaced vertically disposed parallel side members 2, Sci skeleton form. Each side member is provided at the the front, back and outer sides of the members 2,3. 7

The platform 1 is provided lengthwise thereof with a slot 9 (Figure 2) which has its front and rear edges spaced equi-distant from the front and rear edges of the platform. The side edges of the slot 9 are spaced equi-distant from the side edges of the platform. The latter has its side marginal portions formed with tubular bearing seats, as indicated at 10, H, and which are split transversely at their tops. The seats 10, i I at their outer ends are flush with the other side edges of platform I. Positioned within the seats I0, I I, anchored by the holdfast means 12 against the outer side face of and extended outwardly from the members 2, 3 respectively are flanged bearings 13, 13 respectively.

The operating shaft of the apparatus, (Figure 1) is indicated at It and operates a driving connection I5 for a gear pump 16 which is associated with a pump or hydraulic pressure generatorunit 11. A power transmitting shaft is indicated at l8 and is operated from a motor unit 19. The operating shaft 14 is driven by any suitable means, which by way of example, is shown as a pulley 20 having anelongated hub 21 keyed on shaft l4 and abutting collar i3.

The driving connection 15 is of the spiral gear type and is employed for operating the driving means 23 of the gear pump 15 submerged in the reservoir aforesaid, -which is secured to and depends through the bottom of tank 1. The pump 16 discharges hydraulic fluid through the pipe 25 (Figure 16) to the bottom of a filter It, suitably connected to tank 1. The filter is to be provided at its top with a pressure relief valve which returns the surplus fluid tothe reservoir and also carries oft any air bubbles that might be in the fluid. Leading from the filter, not shown, is. a supply line 26 which opens into a fluid distributor valved block 21 commonto the units I1 andiS.

The block 21 (Figures 7, 15 and 21) includes an intake port 28 into which the supply line 26.

opens. The block 21 is formed with a vertically disposed duct 29 opening at its lower end into the port 28 and below its upper end into a channel 30 which is disposed at right angles to the duct 29. The upper end of the latter is closed .by a

plug 3|. The block 21 is formed with a pair of spaced parallel chambers32, 33 between which extends the duct 29. The block 21 in proximity to its bottom is provided with a pair of recesses 34, 35 arranged below the chambers 32, 33 respectively. The recesses 36, 35 communicate with the port 28. The block 21 is formed with a pair of spaced vertically disposed openings 36, 31- which are intersected by the recesses 34, 35 respectively and connect the chambers 32, 33 with the recesses 34, 35-respectively. Plugs 3B, 39 are secured in the lower ends of the openings 36, 31 respectively and constitute stops for the spring controlled relief valves 60, 41 slidably mounted in the openings 36, 31 respectively and extending into the chambers 32, 33. Each relief valve consists of an inverted cup-shaped body part d2 formed at its top with an axial opening 63 which has its wall registering with the inner face of. a tubular stem M integral with the top of body part 62. The stem M intermediate its ends is provided with a seat 65 for a globular check valve 66. The stem M is so formed whereby the inner face of its upper end will align with a vertical outlet port. The outlet ports are indicated at a1, 28 and open at their inner ends into the chambars 32, 33 respectively. The relief valves 88, 8i include controlling springs 49, 58 each of which is interposed between the top of the body part 42 of the valve and a stop 38 or 39. The springs normally maintain the stems of the relief. valve against the top wall of the chambers 32, 33 such as shown in Figure 7. I The block 21 includes a pair of spaced ducts 52 open at their inner ends and plugged at their outer ends and which communicate with the chambers .32, 33. The

ducts 5|, 52 are arranged below the channel 38.

The valves 48, 4| .are of the hollow piston type and are normally seated such as shown in Figure 7.

Communicating with the ports 41, 48 are fluid conducting pipes 53, 54 respectively for a purpose to be referred to. Communicating with the channel 38 is a pair of fluid conducting pipes 55, 56 (Figure 15), for a purpose to be referred to.

The pump unit I1 includes a pair of oppositely disposed inwardly opening parallel rings 51, 58 of channel shape cross section for suspending a circular row of spaced .radially disposed cylinders 59 open at their inner ends and having their sides provided with rollers 68 mounted in the rings 51, 58. Operating in each cylinder 59 is a tubular piston 62. The pistons are fixedly secured at their inner ends to and radially disposed with respect to a revoluble tubular shaft 63 provided between its inner and outer faces with a set of angle-shaped fluid channels 63 opening at their outer ends into the inner ends of the'pistons 62. I

The motor unit I9 includes a pair of oppositely disposed inwardly opening parallel rings 64, 65 of channel shaped cross section suspending a circular row of spaced radially disposed cylinders 66 open at their inner ends and having their sides provided with rollers 61 mounted in the rings 64, 65. Operating in each cylinder 66 is a tubular piston 68. The pistons 68 are fixedly secured at their inner ends to and radially disposed with respect to a revoluble tubular shaft 69 provided between its inner andouter faces with a set of angle-shaped fluid channels 18 opening at their outer ends into the inner ends of the pistons 68. When the pump unit I1 and the motor unit I9 are arranged in relation the inner ends of the passages 63 align in spaced relation with respect to the inner ends of the passages 18.

The shafts 63 and 69 are of like form, but are oppositely disposed and each (Figure 18) includes an inner portion 1| and an outer portion 12 corresponding in outer diameter to that of the portion 1|. Each shaft also includes an intermediate portion 14 of greater outer diameter than the portion 1|. outer periphery with threaded sockets 15 for the tubular pistons 62 or 68. Theportion 12 is of greater inner diameter than the portions II, 14. The inner diameter of the portions 1| 14 are the same.

The portion 12 its outer edge with tion 12 of the shaft of the shaft 63 is formed in coupling teeth 18. The por- 69 is formed in its outer edge with coupling teeth 11. Secured upon the outer face of the portion 12 of the shaft 83 adjacent the teeth 16 is an annular cage 18 provided with bearing balls 19. Secured upon the outer face of the portion 12 of the shaft 69 adjacent the teeth 11 is an annular cage 88 provided with bearing balls 6!. v

The apparatus includes a pair of vertically disposed outer supports 82, 83 of like form-but lower end of the is formed with a vertical tubular portion 99 The portion 14 is provided in its 3 which are oppositely disposed, extend through the slot 9 and are anchored to the platform I. With reference to Figures 22 and 23 each support consists of a. tapered upper part 84, a flared lower part 85 merging at its upper end into the part 84. Integral at the point of mergence of the'parts 84, 85 are oppositely disposed apertured lugs 86, 81 rabbeted, as at 88. The lugs 86, 81 seat on the platform I and also seat against the front and rear edges of the slot 9. Holdfast means 88 are employed for anchoring the lugs 86, 81 to the platform I. of part 84 has a circular enlargement 98 formed with an axial opening 9|. The bottom of the part 85 is formed with a rib 92 having an arcuate central portion 93 and a pair of oppositely disposed enlarged circular horizontal portions 98, 95 which may be termed lugs and each of which opening 96 axially thereof having a' portion of its wall rabbeted, as at 96 Each of said supports is formed with an enlarged opening 91 substantially centrally thereof and annular flanges 98, 98 forming flurn continuations of the opening. Secured in the rabbeted portion 96 of the wall of opening 91 and to the inner face of the flange 98 is abearing member 99. I

The portion 12. of shaft 63 opening 91 in the support 82 the operating shaft driven will operate at its inner end is and is coupled to I4 whereby the latter when the shaft 63. The shaft I4 provided with an enlarged merging at its outer end into a circular disc I88 formed with radially disposed spaced'notches I8I which receive and coact with the teeth 12 of the shaft 63 for coupling shafts I4, 63 together in'a manner to provide for shaft 63 being driven from shaft I4. The portion 12 of shaft 63 encompasses the portion 99 of shaft I4. The bearing balls 19 on portion 12 of shaft 63 have seated thereon the bearing member 99 carried by the support 82. The shaft I I is mounted in the bearing means I3 and includes a collar I8!- whlch is of less diameter than and is-integral with disc I88.

The power transmission element I8 includes a shaft I82 operated from the unit I9 and is shown as having a transmission means I83, shown by-way of example, as a pulley. The shaft I82 is mounted in the bearing means I3 and extends into the opening of the support 83. The shaft I82 consists of an outer part I84, an intermediate part I85 of greater diameter than the part I84 and an inner part I 86 of greater diameter than the part outer end is formed on cumferentially extending row of radially disposed spaced lugs I81 which form the shaft I82 with what may be termed spaced notches. The portion 12 of the shaft 69 I86 of the shaft 12ofshaft 69 engage in the notches formed by the lugs I81 to provide for shaft 69 to couple withshaft I82 for the purpose of driving the latter. The bearing balls 8| on shaft 69 have the bearing member 99 of the support 83 bear thereon.

The upper end is seated on the portion- I82 and the teeth 11 of portion extends into the 16 formed on the portion There is associated with the pump unit or gen- 4- having its upper end provided with an opening Ill. Depending from the bottomof body part H2 is a flared extension I I5 formed at its lower end with 'an opening H6. The body part H2 is offset with respect to the extensions H3, H0. The upper end of extension 3 and lower end of extension II5 are of greater thickness than the remaining portion of the hanger and such ends are of circular form. Secured to the inner edge of the annular body'part II2 is an inwardly extending collar II1 having secured upon its outer face an annular cage II8 provided with spaced bearing balls H0.

There is associated with the hangers I0 I09 a rockable suspension bar or rod I th refor. There is associated with the hangers III], III a rockable suspension bar I2i therefor. The bar I20 is of circular cross section and is formed of a central part I22, a pair of intermediate parts I23, I24 of less diameter than the part I22 and a pair of outer parts I25, I20 of less diameter than the parts I23, I24. The outer terminal portion of the periphery of each of the intermediate parts is provided with threads I21. The bar I2I is of circular cross section and is formed of a central part I20, a pair of intermediate parts I29, I30 of less diameter than thepart I20 and a. pair of outer parts I3I, I32 of less diameter than the intermediate parts. The outer terminal portion of the periphery of each of the intermediateparts is provided with threads I33.

The upper ends of the extensions H3 of the hangers I00, I09 are mounted on the intermediate parts I23, I24 of bar I20 and abut the central part I22 of the latter. Holding nuts I30 engage with the threads I21 on the intermediate parts I23, I20 and abut the upper ends of the extensions H3. The outer part I20 of the bar I20 extends into the opening 9| of the upper end of the part 8410f the .support 82 and the said upper end of part 84 provides a bearing for the outer part I26 of bar I20. 'The bearing for the outer part I of bar I20 will be presently referred to. The bearing balls carried by the hangers I00; I09 have-the inner edges of the rings 51, 50 of the unit I1 bear thereon.

The upper ends of the extensions AB of the hangers IIO, III are mounted on'ai fe-intermediate parts I29, I of bar I2I and abut the central' part I28 of such bar." Holding nuts I engage with the threads I33 on the intermediate parts I29, I30 of bar I2I and abut-the upper ends of said extensions. The outer part I3I of the bar I2I extends into the opening 9I of the upper end of the part 80 of the support 83 andthe said upper end of the part 00 provides a bearing for the outer part I3I of bar I2I. The bearing for the outer part I32 of bar I2I will be presently referred to. The bearing balls carried by the hangers H0, rings 00, 65 of the unit I9 bear thereon.

The'unit I1 is of the hangers I08, I09. The unit I9 is arranged between the body part of hangersIIIi, III. Arranged between the extensions II5 oi the hangers I00, I09 is 'a spacer block I30 which is pivotally mounted upon a headed bolt I01 seated in the openings IIS and secured to said extensions by a holding nut I30; Arranged between the extensions II5 of the hangers IIO, III is a spacer block, I39 which is pivotally mounted upon a headed; bolt I seated in the openings IIO oi suchextensions and secured to said extensions by a holding nut MI. The bolt I31 connects the lower ends of the hangers I08, I09 together. The

' pockets I5I, I52 inwardly to body part I43 by a III have the inner edges of the.

arranged between the body partarcane bolt I39 connects the lower ends of the hangers H0, IIItogether.

A stationary fluid flow control structure I02 (Figures 6 and '7) is interposed between the hangers I09 and H0 to provide for thecontinuous flow of fluid between units I1 and I9 when these latter are shifted laterally with respect to the axis of the shaft It. The structure I02 also functions for another purpose to be referred to. The structure I32 includes a body part I33 which oppositely tapers from its transverse median to its ends I00, I05. The end I00 is enlarged, of

circular contour and formed with an axial opening I00 into which the inner parts I25, I32 of 'bars I20, I2I respectively extend whereby the end I00 of body part I03 provides a bearing which is common to said inner parts I25, I32. The structure I42 depends through the slot or opening 0 and is formed substantially centrally thereof with oppositely disposed laterally extending apertured lugs I31, lid-which seat on and are anchored to platform I by the holdfast means I09. The body part I03 centrally thereof is formed with an enlarged circularopening I having its wall cut out at diametrically spaced points to form adjacent the side faces of body part I03. The latter is provided with an upstanding angle-shaped channel formed of upper and lower branches I54, I respectively disposed in angular relation. The branch I55 at the lower portion of one side thereof opens into the pocket I5I and is closed at its upper end by a plug I5I A tubular coupler I56 is secured in body part I03 and opens into the lower end of branch I54. A tubular coupler I55 is secured in snugly bearing against the wall of opening I50.

The core and bands are secured together to prevent their revolving relative to each other and ing threaded engagement with body part I03 and extending into opening I50, through the bands and engaging in the core. The member I00 is arranged below the lugs I30 and is re-\ movably secured in position. The bands are formed with openings I6I for the passage and the core is formed with a socket I02 to receive the inner end of member I50. At diametrically opposed spaced points of the flow transfer element, the bands are formed with groups of sets of spaced aligning openings. one of the groups are indicated at I53 and the openings of the other group at I00. The group of sets of openings I03 communicateat the outer end of the group with the pocket IM and at the inner end of the group with a large fluid passage I05 which is formed in the core. The group of sets of openings I communicate at retaining member I00 hav- The openings of the outer end of-the. group with the pocket I52 relation, of arcuate contour and oppositely disposed. The band I59 may be termed the body e to shafts 63, 69 in a manner to be referred to.-

Although the transfer element is shown as consisting of a series of annular parts and a circular part, yet it is to be understood that it may be set up as a one-piece body. The core axially within opening I11 at each end thereof is a. closure thereof is formed with an opening I61.

The band I59 is of greater width than the core I51 and bands I51, I58. The edges of the band I59. are flush with the side faces of body part I43. The edges of the bands I51", I58 andthe sides of the core are flush. The core I51, band I51 and band I58 are spaced inwardl adjacent the side faces of body part I43.

The shafts 63, 6 9 at their inner ends-extend into the band I59 and abut the sides of the core I51 and the edges of the bands I51, I58. The inner ends of certain of the channels 63 10 register with the passage I65 and the inner ends of the other of the channels 63, 10 register with the passage I66. The passages I65, I66 permanently establish communication between the channels 63 and the channels 10.

The shafts 63, 69 are connectedtogether and to the structure I42 by a headed threaded bolt I66 extending through opening I61 in core I51 and through the portions II, I4, of shafts 63. 69 and into the portions 12 of said shafts. The head of bolt I66 bears against the tapered cutout part I66 at the outer end of the portion 15 of shaft 63. The bolt I66 carries a holding nut I69 arranged within the portion 12 of shaft 69. Mounted on bolt I 6 inwardly of nut I65 is a cage I66 carrying bearing balls I66 which bear against the wall of the cutout portion I66 at the outer end of the portion I2 of shaft 69. The bolt I66 is fixed to shaft 63. The shaft 69 revolvcs about bolt 966.

There is associated with the unit I1 a shifting mechanism or hydraulic pressure operated follow up control intensifier I63 for moving the rings 59 of such unit in unisonofi' center in opposite directions. There is associated with the unit I9 a shifting mechanism or hydraulic pressure operated follow up control intensifier I68- for moving the rings 68, 65 of such unit, in unison off center in one direction. The said shifting mechanisms may also be termed hanger adjusting means or hydraulic intensifiers and are referred to in the claims as hydraulic pressure operated valve-controlled adjusting means or structures. The said mechanisms are of' like form, with this exception that each includes a horizontally disposed piston formed with a transverse groove opening at its top, but the groove in the piston I 69 of the mechanism I68 is positioned, with respect to the length of piston I69 at a different point than the position of the groove of the piston I of the mechanism I68 with respect to the length ofthe piston I70. The groove in piston IE9 is indicated at III and the groove in piston I10 at I12. The groove III isarranged at the transverse center of piston I69.

The groove I12 is arranged between the transverse center and one end of piston I10.

The mechanisms I68 and I68 each include a pair of spaced endwise aligned cylinders I13, I70 open at their inner ends in which is slidably mounted the piston of the mechanism. The piston is cut away at each side to form it with a reduced intermediate portion I which is of greater length than its end portions I16. Thereduced portion-I15 of piston I69-is arranged between the lower ends of the hangers I08, I09 and has seated in its groove "I the spacer block I36. The reduced portion I15 of the piston I10 is arranged between the lower ends of the hangers III), III and has seated in its groove I12 the spacer block I39. Each piston is formed below the bottom of its groove with an opening I11 extending from end to end thereof. Secured .of oppositely extending spaced endwise'aligning' ducts I80, I8I lengthwise thereof opening at its ends. Each piston is formed with a pair of spaced parallel vertical ducts I82, I83 which are closed at their upper ends by the plugs I84, communicate at their lower ends with the opening I11 andintermediate their ends with the inner ends of the ducts I80, I8I. Each piston is provided with an exhaust port I85 which leads from the opening I11 to its top. Each piston centrally of its bottom is cut out, as at I86. to provide a clearance for a purpose to be referred to.

The cutout I86 communicates with the opening I11. The latter has slidably mounted thereon. a combined fluid controlling and conducting valve element I 81 formed in its top with a groove I88 lengthwise thereof which associates with a part of the top of the wall'of opening I11 to form an exhaust conducting passage opening into the lower end of port I85. The groove I88 is of less length than and has its .ends spaced from the ends of element I81. The latter is provided with a fluid conducting channel I89 which extends from end to end thereof. The element I81 centrally of its bottom is formed with anopening I90 communicating with the channel I89. Secured to element I81, extending into the opening I90 and seated in a mortise I9I formed in the bottom of element I81 is a fluid supply element I92. The latter depends from element I81 and has a part of its head I93 arranged in and is of lesslength than cutout I86 in the bottom of the piston. The element I92 includes a stem I94 and a port I95 which extends from a point above the bottom of stem I94 through the head I93 and opens into the channel I89. Surrounding the stem I94 is a sleeve I96 formed with a'pair of oppositelyextending arms I91, I98. The stem I9'9 is formed with a port I99 which opens into'the lower end of the port I95. The arm I98 is tubular and constitutes a fluid conductor and has its inner end communicating with the port I89. The arm I91 hassecured to its outer end an extension 200 formed with a globular end 200 for a purpose to be referred to.

The cylinders I13, I14 are connected together by a pair of horizontally disposed oppositely extending U-shaped arms I, 202 which are offset with respect to said cylinders. The arm 20f at its corners is formed with vertical openings 203. The arm 20I centrally thereof is formed witha vertical opening 204. The arm 202 cenconstitutes a check valve housing. The member 209 is open at its lower end and has its closed top 208 provided with a positioning pin 2I0. The member 209 is formed in'one side with a fluid outlet 2I I. The member 209 at its lower end is formed with a laterally extending annular flange 2I2. The member 209 is formed therein near its upper end with a valve stop 2I3. There is associated with the member 209 a tubular coupling nipple 2I4 provided intermediate its ends with a peripheral polygonal shaped flange 2I5. The nipple 2I4 consists of an outer peripherally threaded tubular part 2I6 and a tubular inner part 2 I 1 of less outer diameter than the outer part 2I6. The part 2I1 has an enlarged portion 2"! which threadedly engages the inner face of the member 209. The other portion of the part2l1,

indicated at 2I9, is spaced from the inner face of the member 209. The part '2I9 at its upper end is provided with a valve seat 220 for check valve 22I of globular contour. The flange 2| 5 on the nipple 2I4 abuts the flange 2I2 on the member 209.

. The arm I98 which extends from the sleeve I96 has formed integral with its outer end a sleeve 223. The arm I98 opens into the sleeve 223. The latter encompasses the member 209 and seats on the flange 2i 2. The sleeve 223 revolves about the member 209 and fluid from the member 209 passes therefrom into the arm I98 and is conducted to the element I81 and from there into the opening I11. The nipple 2 of the mechanism I68 opens into the pipe 55. The nipple 2i4 of the mechanism I68 opens into the pipe '56. The pipes 55, 56 extendfrom the valve distributor block 21 andhave threaded engagement with the parts 2I6 of the nipples I24 of the mech-.

anisms-i68, I68. The arm 20I of the mechanism I68 is secured to the lower end of the support 92 by the holdfast means 224 extending through the openingsat the lower end of the support 82 and the openings at the corner of the'arm. The arm 20I of the mechanism I68 is secured to the lower end of the support 83 by the holdfast means 225 extending through the openings at the lower end of the support 83 and the openings at the corner of the arm.

There isas sociated with the mechanism I68,

l68 'a control mechanism 226 for the valve elements'l81 for controlling the direction of shift of the pistons I69, I in opposite directions by the fluid for adjusting the positions of the units l1, I9. The mechanism 226 includes an upstanding support 221 secured tothe front.of pan 1 and which is formed at its upper end with a bearing 228 in. which is mounted a rock shaft 229. The latter extends from each end ofbearing 228 andv has, fixed on an end terminal portion thereof a handle 230'. Secured on the other end terminal portion of the shaft 229 is the sleeve 23I which is secured to one face of a disc 232 axially of said-face. The sleeve 23-I abuts against the bearing 228. The disc 232 is formed with a pair of pins 233 and 234 disposed in spaced relation a distance substantially 90 degrees with respeot to the disc. The pins are arranged in close proximity to the edge-of the disc. The pin 233 extends from one face of the disc and the other pin 234 from the other face thereof. The pins have globular outer ends as indicated at 235, 236. The. head of pin 235 and the head of pin 236 each extend into a sleeve and the said sleeves are indicated at 231, 238. The pins are universally connected to their sleeves and the structural arrangement to provide such connection is shown in Figure 14 with respect to pin 283. The sleeve 231 has a tapered end portion 239 of greater thickness than its remaining portion 240. The portion 239 is internally threaded and such portion provides the sleeve with an internal shoulder 5 24!. The portion 240 of sleeve 231 has one side formed with an elongated slot 242. Threadably engaging with the interior of the portion 240 at one end thereof is a plug 283 having its inner end formed with a concave recess 264. The plug 243 10 for a portion of its length is slotted, as at 245, and

extending through theslot, as well as through the portion 240 is a holding pin 246 for plug 243. Arranged within the portion 240 of sleeve 231 is a plunger having a head 241 provided with a con- 15 seated in the recesses. The pin 234 is mounted in its sleeve 238 in the same manner as the pin 233 is mounted in its sleeve 231. Connected to the portion 239 of the sleeve 231 The is a control or shifting rod I leading to the unit .80

I1 and which has mounted thereon a holding nut 252 which bears against the portion 239 of sleeve 231. The outer end of the rod I has threadable' engagement with the portion 239 of the sleeve :31. The rod 25: is connected to the inner end of sleeve 231. The plug 243 is arranged in the outer end of the sleeve 231.

Connected to the portion 239 of the sleeve 238 is a control or shiftingrod 253 leading to the unit I9 and which has mounted thereon a holding o nut 254 which bears against the portion 239 of sleeve 238. The rod 253 has threadable engagement with the portion 239 ofthe sleeve 238. The outer end of the rod 253 is connected to the inner end of sleeve 238. The plug 243 is arranged in the outer end of the sleeve 238.

The extension 200 on the arm I91 of the mechanism I68 is connectedwith the inner end of the rod 25I in the same manner as the pin 233 is connected with the outer end of the rod 25I.

The extension 200 on the arm I91 of the mechanism I68 is connected with'the inner end of the rod 253 in the same manner as the pin 234 is connected with the outer end of the rod 253.

As before stated, the pistons I69, I10 are of u the same form withthe exception as to the position of the grooves I1I, I12. The groove "I being I at the center of piston I69 for the pump or generator unit- I1 allows the travel to be of equal or reverse pumping action with variable volume in proportion to the length of movement. The groove I12 being adjacent or oilset relative to one side of the transverse median of the piston limits each side of the center, giving! forward I10 for the motor unit will not carry the motor 05 unit I9 across center. The piston-I10 is connected to the control so that it keeps the motor unit I9 in a full throw position until the piston I69 has moved to full throw either side of center. Any further movement of the control will 70' pull the motor unit I9 towards center reducing the throw and causing a further increase in speed. With reference to Figure 17 'the control or shifting rod 25B to the pumping or generating unit I1 is at'full movement of the crank disc 1 while the control or shifting rod 253 to the motor unit I9 is on dead center. This is the neutral point of the control. The transmission is'never brought] to zero stroke position.

When the pumping unit I7 is 'centered it has no discharge. When the motor unit I9 is in full throw but standing dead, it is receiving no fluid from the pump. Any movement of the control in either direction will cause a throw in the pump unit I7 and the latter will discharge forward or reverse accordingly into the unit I9 producing rotation in proportion to the movement of control. Upon continued movement of control, the pump unit control rod will go into dead center and the motor unit control rod will come into full movement. No matter in which direction one moves the control, a continued-movement will reduce the motor volume causing a further increase in speed.

Any movement of the throw control piston for unit I 7 will swing the unit and move the rings 57, 58 in unison off center or eccentric with respect to shaft 63. This statement applies to the motor unit III as the rings 64, 65 will be-moved off center or eccentric with respect to shaft69 when the throw control piston for the element I9 is moved. With respect to each unit when revolving, the pistons and cylinders thereof will travel around different centers causing the cylinders to move in and out on the pistons in each revolution or if connected in a hydraulic circuit they will receive fluid one-half of a revolution and discharge the other half.

With reference to Figure 1, it will be assumed that the operating shaft I6 is connected with and driven from a source of power and which in turn will operate the unit I7, as shaft II is connected to the latter. The shaft II will also operate the driving connection I5 for the pump I6 and on the operation of the latter it provides for the fluid to be supplied to the valve distributor block 27. The fluid 'enters block 27 at port 28, passes up through duct 29 into the channel 30 and from the latter into the lines 55, 56 which open respectively in the mechanisms I68, I68 whereby the fluid is supplied to the elements I67 of said mechanisms and from said elements into the cylinders for pistons I69, I70. When the fluid enters an element I67, it may discharge from either end thereof into a cylinder I73 or I76, depending upon the position of element I87 relative to ports I82,

I83. If the element I87 is moved to the left, the

ports I82, I83 will be opened and will cause the cylinder I73 to communicate with the atmosphere through port I85. The fluid then can pass through ports I83, WI and fill the cylinder I76 at one end of the piston.

Now with reference to piston I69, the pressure of the fluid in cylinder I74 will move piston I69 in a direction towards cylinder I73 until the ports H32, I83 are again closed. In this manner the piston- I69 will follow'the element I87 in any direction in which the latter may be moved, and an equal distance, and it will not change its location independent of element I87.

A movement of the piston I69 swings the lower end of the hangers I08, I 09 which carry the rings 57, 58 therewith whereby these latter will swing off center and cause the cylinders 59 to travel in an eccentric path in relation to the pistons 62. A similar operation is had when a shift is given to the piston I70, that is to say, the latter swings the lower end of the hangers I I0, I I I which carry the rings 64, 65 therewith whereby these latter will be swung off center and cause the cylinders 66 to travel in an eccentric path in relation to the pistons v68. I With reference to Figure 18, it will be assumed that the unit I7 is being driven by some source of power and'the control therefor is in its-forward position, the cylinders of the unit,- due to the action of piston I69 will run-eccentrically to the pistons of the unit. Cylinder A of unit I7 will be driven inwardly onpiston B. This will cause a discharge through channel C, through passage D, through channel E,-through piston F ofunit I9 and act on cylinderG of unit I9 which is in full throw or eccentric position. This action causes unit I9 to rotate. The fluid being received in one-half revolution is carried around and is discharged through channel H, through passage I, through channel J and into the unit l7.

Moving the control into reverse, throws the unit I7 off to the opposite side of center causing it to discharge at channel J and to drive the unit I9 in the opposite direction. The unit l7 discharges a volume in proportion to the distance it is taken off center and in this manner gives a variable speed to the unit I9 in either direction. The control is so arranged that after the unit l7 has reached its maximum throw in either direction, continued movement of the control acts on the piston I70 of the unit I 9 moving the latter towards center. This has the effect of shortening the stroke or reducing the volume of the unit. I9

giving a further increase of speed at a sacrifice of torque.

With reference to Figure 7, when the transmission is in operation with the unit I9 running cates with the return or suction side .of unit l7.

If the control is moved into reverse, the passage use will become the pressure port holding valve 86 of relief valve II on its seat and the make-up fluid will pass valve 66 of the relief valve 40. Should the unit I9, running in a forward direction with the pressure acting to hold valve 46 of the relief valve 46 on its seat. become overloadedthe pressure will rise to a point where the valve 49 will be unseated, the pressure will enter chamber 32 and pass through the ducts 5!, 52 into the chamber 33, having entered there the pressure will act simultaneously on the larger diameter of the relief or overload, valves 80, 6|, thereby compressing the springs 39 50 and drive said valves against the stops 38, 39. This allows for a circulation of the fluid from the pump to pass through the pipes 53, 54 with the unit I9 standing stationary. Upon moving the control to the center or neutral position, the valves II), I will close ready for operation when the overload is removed from unit I9. This overload action will operate in either forward or reverse direction of operation of unit I9.-

The arms 202 of the mechanisms I68, I68 are detachably connected to the body part I43 of the structure I42 by spaced holdfast means 254 carried by the lower end of body part I 43 and ex.-

tending through the openings 295 in arms 2 02.-

The band I59 of the laminated fluid flow controlling element carries bearings means 255 for the inner ends of the shafts 63, 6.9.

The pump or generator unit I1 and the motor unit I9 each includes what may be termed a circular gang of radially disposed tubular pistons bodily travelling in a circular path and a circular gang of radially disposed spaced cylinders bodily travelling in a circular path and slidably mounted on the pistons of the gang. The pistons are connected to a revoluble shaft. The cylinders of the gang carry means for slidably' suspending them from a pair of oppositely disposed channeled shaped rings and with the latter mounted on bearings supported by a pair of adjustable hangers coacting, when adjusted with the pair of rings for disposing the axis of the gang of cylinders offset with respect to the axis of the gang of pistons whereby the path of travel of the cylin-' ders will be disposed in eccentric relation with respect to the path of travel of the pistons.

The improved form of cylinder is shown in detail at 59, Figures 11, 12 and 13. This form of cylinder is unlike the conventional form now employed and has a square outside which is closely fitted between the cylinder retaining rings 51 and 58 Figure 13, keeping the two integral oppositely .disposed roller journals at right angles to the retaining rings 51 and 53, thus eliminating the necessity for any cross heads or other guiding means. .The elimination of cross heads or other guiding means enables the retaining rings as shown-at 51 and 58 Figure 18,-to be greatly reduced in diameter, allowing the cylinder heads to extend well beyond into the open for heat dissipation. The greatest temperature rise in hydraulic transmissions of this class occurs in the cylinder chambers, therefore, it is important to keep the chambers as far removed from the masses as possible. The retaining rings 51 and 58 are journaled on the bearings H9 and rotate bodily with the cylinders as one mass. The rollers 6i! do not roll continuously in the retaining rings but have only an oscillating movement to compensate-for uneven cylinder spacing when the cylinders are travellinga circular path that is eccentric to the common center of the unit. The bearings II3 are fixed in the hangers I06 and I09 for the pump. The motor unit has the same construction, the hangers are shown at IIO and I I I, the upper portion of these hangers are-flxedto the pivot shafts I26 and I2I. The lower portions 'of the hangers for the generating or pump unit and for the motor unit terminate on the control int'ensifiers I63, I68, which have the ability to change the stroke of the cylinders at the will of the operator by swinging the hangers. The control intensiflers I'I4 areactuated through the means heretofore referred to. impart the movement of the actuating rods to the cylinder hangers. The control rod I is connected to the pump stroke control actuating means and to the live center of the rock shaft disc 232, in this position the control is holding the pump unit on center or its neutral point so that it will not discharge any fluid to the motor in either direction. The control rod 253 is connected to the motor stroke control actuating means and the dead center of the rock shaft disc 232, in this position the control -is holding the motor unit in full throw position, ready to give maximum torque for any fluid received from the pump. By referring to Figure 1'7 it can be readily understood that any movement in either direction given the rock shaft disc 232, will have an immediate effect on the pump control, but due The intensifiers,

to the fact that the motor control is on dead center it is not immediately effected, but a continued movement in either direction will have the same effect of shortening the motdr'stroke, which should be limited at a point where the displace-' ment of the motor is one-halfthat of the pump. When operating a hydraulic transmission such as described, it is necessary to have a device or structure which includes a fluid by-pass channel incorporating an overload valve, introduced into the hydraulic circuit, which will by-pass the discharge from the pump in case of a sudden overload. This device which has been heretofore described also acts to greatly reduce the fluid presv sure in the by-pass circuit, which prevents an undue temperature rise in the fluid-before the load can be removed. Figures 7 and 21 show the structure of this device in which the block 21 is the body of the device incorporating two piston type valves 40 and M, these valves have an extended stem or seat 44 of a much smaller diameter, within this extension is a ball check valve 46, the purpose of which will be hereinafter described. The conducting pipes 53 and 54 are shown connected at the top of block 21, these pipes also connect into that portion of the housing or frame surrounding the fluid transfer element or valve, as shown in Figure 7, establishing communication between the valves 40 and 4| and the transfer ports I65 and I66, through fluid channels or ports I63 and I64. During the operation of this transmission the transfer ports I65 and I66 constitute the two sides of the hydraulic circuit, namely the high pressure or discharge side from the pump, and the low pressure or return side, neither ports I63 or I64 being speciflcally the high or low pressure side as the circuit is reversed when the pump throw is moved across center to produce reverse rotation in'themotor unit. It is also necessary to feed a small quantity of fluid into the circuit to make up that which is lost through leakage in operation, owing to this fact. I have made the valve block 21 act as a centralized distributing means for the fluid from the pump I6. The outlet 25 from pump I6 leads to the bottom ofthe filter I6. When the inputshaft I4 is being driven there is a continuous flow of fluid into the filter, the unused surplus being returned to the reservoir 1 through the pressure regulating valve, not shown, mounted at the top of the filter so as to carry off all air that might become mixed in the fluid. The primary object of this regulating valve being to maintain a definite working pressure on the fluid within the filter; The working fluid is taken from the bottom of the filter through the fluid supply line 26 connecting into the valve block 21. Referring again to Figure2l the fluid upon leaving the filter enters valve block 21 at point 28, fluid used in the stroke control intensifier passes upward through fluid channel 29 entering the channel 30, and subsequently enters the conducting pipes 55 and 56 which are connected to the nipples 2I4. The ball check valve 22I acts to'prevent any fluid back surge from the inten- -sifier, after passing this check valve the fluid passes through the outlet 2 into the actuating arm or lever for conducting the fluid to the fluid supply element I92. The fluid ntersthe inten;

Going back to the fluid intake port 26 in valve block 2'|, fluid entering here will fill the recesses or chambers 34 and 35 under the piston valves aware i I i acent to its side faces with a core adapted to a high pressure port will be held to its seat, while the other will open and allow leakage makeup fluid to pass into the low pressure side of the circuit.

To set forth the action of the overl valves, I

will assume that the rotation of the motor unit is such that transfer, passage or port 966, Figure 7 is the pressure passage or port and it was driving a machine in which the operator for some accidental reason or otherwise allowed an overload to occur. The pressure in passage or port I65 will instantly rise to such a point that it will act back through the fluid conducting pipe 53 to unseat the overload valve at at point 34. The fluid will enter chamber 32 and pass, through the ducts or fluid channels at and 62 to chamber 33, at this point the fluid will act on the large diameter of the valves st, ti throwing them both wide open allowing the fluid to pass back to transfer passage or port the, through the conducting pipe dd. Due to the difference of the two diameters on the valves in which the ratio of area is about five to one, the fluid pressure will drop to one-fifth of the original pressure in maintaining an open by-pass channel; this prevents heating of the fluid until the operator can place the pump unit in neutral crank position and remove the cause of overload.

Where hydraulic mechanisms of this class are applied to machine tools; etc., the operator is required to make many changes of speed or reversals of rotation. Due to the force required on the controls in manipulation, the common practice is to use hand wheels and threaded shafts, which are slow and'tiresome. To. overcome this, I have placed the shifting mechanisms or hydraulic intcnsiflers ltd, itt 'in the control systerm which furnishes the necessary force to quickly follow up the almost eflortless movements of the operator. The hydraulic fluid, under pressure from the pump it, enters the actuating supply element is? at the port E99, passing upward through port 695 into channel ta which emerges from both ends of the element it'd, placing it in hydraulic balance. The piston ltd has two fluid channels ltd and idi which communi= cate between the cylinder chambers and the opening ill through channels E82 and its, but are sealed by the element 95?. When-forming the groove me, a mass is left at each end of the element I87, which exactly covers the ducts i552 and its. If the'element it'll is moved endwise, it

will put onecylinder chamber in communication with the outside, so that its fluid can be discharged, and the other with opening i "it, from which it will receive fluid causing the piston ltd to follow the movement of the element it'll until the fluid ducts it? and 583 are again closed. This device is also self-locking in that the piston use will not move under any force less than enough to overcome the hydraulic fluid pressure unless the element it? is moved flrst.

What I claim is:

i. In a' hydraulic transmission of that type having a pivotally suspended driven revoluble' adjustable hydraulic pressure generating t, a pivotally suspended revoluble controllable motor unit driven from the pressure generated from the other unit and with each or said units including a shaft formed with fluid channels w I. =1 r at the inner end thereof. the combination of an upstanding fluid trer element adapted to encompass the t portions of said shafts, said element w- 1 formed oi a stationary body provided centrally thereot and inwardly be arranged between and against the inner ends of said shafts whereby the; latter will be encompassed by said body, said core being formed with a pair of spaced fluid passages of 'arcuate form for registering with the channels of said shafts, said body being formed with pockets spaced from said core and communicating with said passages, bearings within said body and interposed between the latter and said shafts,v pipes opening into said pockets to provide to. a. circulation of fluid through said element and units, a hydraulic pressure operated adjusting means for and adapt= ed to be connected with the generator unit for selectively controlling the direction of flow through such unit, a hydraulic pressure operated valve-controlled adjusting means adapted to com meet with the motor unit for controlling the speed of the latter, a valve-controlledv fluid conducting pipe leading to each of said adjusting means, and a fluid distributor adapted to com municate with a source of fluid supply opening into the pipes leading to the pockets of the fluid transfer element and the pipes leading to the pair of adjusting means and being provided therein with valves for controlling the pipes opening into thepockets.

2. In a. hydraulic transmission. two spaced pairs of spaced upstanding hangers, independent means for pivotally suspending each pair of hangers from their upper ends, a pivotally mount-w ed spacer block connected with and arranged between the lower ends of. each pair of hangers, the hangers of a pair being adjustable in unison, a driven, controllable, bodily revoluble, adjustable hydraulic pressure generating unit carried by a pair of hangers, a bodily revoluble controllable,

adjustable hydraulic pressure operated motor unit operated from the pressure generated by the other unit and carried by the other pair of hangers, each of said units including a pair of parallel parts revolubly mounted on and intermediate the ends of the inner sides of a pair of hangers and outwardly and inwardly extending parts passing through and spaced from the body of such pair of hangers intermediate the ends oi the latter, the said inwardly extending parts being inner endwise aligned, oppositely'disposed and formed lengthwise with fluid channels opening at the inner ends of such parts, a stationary element arranged between and encompassing the innerend terminal portions of the said inwardly extending parts and having an inset core formed with spaced fluid transfer means registering with the said inner ends of the channels, a valvecontrolled hydraulic pressure operated adjusting means for and engaging with and shifting the spacer block for the hangers carrying the generator unit for selectively controlling the direction of flow through the latter, a valve-controlled hydraulic pressure operated adjusting means for and engaging with and shifting the spacer block for the pair of hangers for the motor unit for controlling the speed of the latter, and controlling means for said adjusting means 3. In a hydraulic transmission, a supporting means including a platform provided with a lengthwise slot, a pair of spaced upstandingi aligned outer supports anchored inte mediate their ends to said platform and depending through said slot, an upstanding stationary fluid till flow control structure arranged between,-spaced pending through said slot, a pair of spaced up- 

